I first conducted a stream survey of North Creek in 1978. Then, it flowed all year-long from its headwaters next to what is now Evergreen Way in Everett, downstream through Snohomish County’s McCollum Park and what is now the City of Mill Creek, into the Canyon Park and Bothell Business Centers, and past what is now the University of Washington Bothell campus into the Sammamish River.
In the fall of 1978, there were so many salmon swimming upstream in McCollum Park it looked like you could walk across their backs from one side of the creek to the other. The areas of vegetation next to the stream, called riparian zones, were several hundred feet wide throughout much of the watershed and most wetland areas were functioning.
The North Creek flow stopped in McCollum Park for a few weeks during the summer of 1987. Over the next few years, the creek went dry in the park for increasingly longer periods. Now, there is no stream flow between mid-May and the end of October.
The lack of rain during the last few summers is a factor. However, the primary cause of no stream flow in the upper two miles of North Creek is conversion of forests and wetlands in the surrounding watershed to residential and commercial development and significant reduction of the “riparian zone” width. In local government regulatory speak, “riparian zones” are referred to as “buffer areas.”
Now, over 60% of the upstream watershed is covered with housing developments, shopping centers, roads and other hard surfaces that prevent rainfall from soaking into the ground. And most of the riparian zone from Evergreen way to McCollum Park has been lost. Not surprisingly, North Creek’s once abundant salmon run observed in McCollum Park has disappeared.
Making matters worse for salmon and future winter flooding events, in May 2025, the Snohomish County Council amended the County’s Critical Areas Regulation (CAR) to allow for the filling of small wetlands and to reduce “buffer” sizes between new development and streams.
That action was challenged to the Washington State Growth Management Hearing Board (GMHB) by Futurewise, League of Women Voters of Snohomish County, Pilchuck Audubon, Sno-Isle Chapter of the Sierra Club, and the Adopt A Stream Foundation (AASF).
On February 17, 2026, the GMHB found that Snohomish County’s new CAR riparian buffers did not protect the functions and values of critical areas and incorporate best available science. Snohomish County was directed to address those issues by the end of 2026.
The primary matter at hand is the size of “buffers” between new development and streams and wetlands. We recommend the Council follow the Department of Fish and Wildlife’s guidance:
The riparian buffers should be the width of the riparian ecosystem estimated by one 200-year site-potential tree height (SPTH) measured from the edge of the active channel or active floodplain, whichever is wider.
The functions must be protected within at least one 200-year SPTH because it is a scientifically supported approach to protect and maintain full function of the riparian ecosystem including salmon habitat. To make the regulations easier to manage, the county should use 200 feet as the 200-year SPTH.
In addition, I recommend that all new construction adjacent to critical areas must be designed using low impact development techniques.
The County’s Planning Commission (PC) will be briefed on the matter and conduct a Public Hearing scheduled for 5:30pm Tuesday October 27 and then prepare recommendations for the County Council to consider. Sorry for the very short notice – we just learned of this “critical” public hearing date a few days ago.
You are encouraged to share your thoughts to the PC on protecting Snohomish County streams in person at the hearing or online. For details go to PC website: https://snohomishcountywa.gov/164/Planning-Commission.
The County Council hearing is not yet scheduled. To ensure that you are notified of that hearing date, call the Council’s office at 425-388-3494, ask to become a party of record and to receive notice when that Critical Areas Regulation hearing is scheduled.
Tom Murdoch is the director emeritus for the Adopt A Stream Foundation. www.streamkeeper.org
Tom Murdoch, Adopt A Stream Foundation Director Emeritus & Co-author of the Streamkeepers Field Guide: Watershed Inventory and Stream Monitoring Methods
